/*
 * $Header: /home/jerenkrantz/tmp/commons/commons-convert/cvs/home/cvs/jakarta-commons//httpclient/src/java/org/apache/commons/httpclient/methods/InputStreamRequestEntity.java,v 1.4 2004/05/17 21:46:03 olegk Exp $
 * $Revision: 480424 $
 * $Date: 2006-11-29 06:56:49 +0100 (Wed, 29 Nov 2006) $
 *
 * ====================================================================
 *
 *  Licensed to the Apache Software Foundation (ASF) under one or more
 *  contributor license agreements.  See the NOTICE file distributed with
 *  this work for additional information regarding copyright ownership.
 *  The ASF licenses this file to You under the Apache License, Version 2.0
 *  (the "License"); you may not use this file except in compliance with
 *  the License.  You may obtain a copy of the License at
 *
 *      http://www.apache.org/licenses/LICENSE-2.0
 *
 *  Unless required by applicable law or agreed to in writing, software
 *  distributed under the License is distributed on an "AS IS" BASIS,
 *  WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
 *  See the License for the specific language governing permissions and
 *  limitations under the License.
 * ====================================================================
 *
 * This software consists of voluntary contributions made by many
 * individuals on behalf of the Apache Software Foundation.  For more
 * information on the Apache Software Foundation, please see
 * <http://www.apache.org/>.
 *
 * [Additional notices, if required by prior licensing conditions]
 *
 */
package org.apache.commons.httpclient.methods;

import java.io.ByteArrayOutputStream;
import java.io.IOException;
import java.io.InputStream;
import java.io.OutputStream;

import org.apache.commons.logging.Log;

/**
 * A RequestEntity that contains an InputStream.
 * 
 * @since 3.0
 */
public class InputStreamRequestEntity implements RequestEntity {

	/**
	 * The content length will be calculated automatically. This implies
	 * buffering of the content.
	 */
	public static final int CONTENT_LENGTH_AUTO = -2;

	// private static final Log LOG =
	// LogFactory.getLog(InputStreamRequestEntity.class);

	private long contentLength;

	private InputStream content;

	/** The buffered request body, if any. */
	private byte[] buffer = null;

	/** The content type */
	private String contentType;

	/**
	 * Creates a new InputStreamRequestEntity with the given content and a
	 * content type of {@link #CONTENT_LENGTH_AUTO}.
	 * 
	 * @param content
	 *            The content to set.
	 */
	public InputStreamRequestEntity(InputStream content) {
		this(content, null);
	}

	/**
	 * Creates a new InputStreamRequestEntity with the given content, content
	 * type, and a content length of {@link #CONTENT_LENGTH_AUTO}.
	 * 
	 * @param content
	 *            The content to set.
	 * @param contentType
	 *            The type of the content, or <code>null</code>.
	 */
	public InputStreamRequestEntity(InputStream content, String contentType) {
		this(content, CONTENT_LENGTH_AUTO, contentType);
	}

	/**
	 * Creates a new InputStreamRequestEntity with the given content and content
	 * length.
	 * 
	 * @param content
	 *            The content to set.
	 * @param contentLength
	 *            The content size in bytes or a negative number if not known.
	 *            If {@link #CONTENT_LENGTH_AUTO} is given the content will be
	 *            buffered in order to determine its size when
	 *            {@link #getContentLength()} is called.
	 */
	public InputStreamRequestEntity(InputStream content, long contentLength) {
		this(content, contentLength, null);
	}

	/**
	 * Creates a new InputStreamRequestEntity with the given content, content
	 * length, and content type.
	 * 
	 * @param content
	 *            The content to set.
	 * @param contentLength
	 *            The content size in bytes or a negative number if not known.
	 *            If {@link #CONTENT_LENGTH_AUTO} is given the content will be
	 *            buffered in order to determine its size when
	 *            {@link #getContentLength()} is called.
	 * @param contentType
	 *            The type of the content, or <code>null</code>.
	 */
	public InputStreamRequestEntity(InputStream content, long contentLength,
			String contentType) {
		if (content == null) {
			throw new IllegalArgumentException("The content cannot be null");
		}
		this.content = content;
		this.contentLength = contentLength;
		this.contentType = contentType;
	}

	/*
	 * (non-Javadoc)
	 * 
	 * @see org.apache.commons.httpclient.methods.RequestEntity#getContentType()
	 */
	public String getContentType() {
		return contentType;
	}

	/**
	 * Buffers request body input stream.
	 */
	private void bufferContent() {

		if (this.buffer != null) {
			// Already been buffered
			return;
		}
		if (this.content != null) {
			try {
				ByteArrayOutputStream tmp = new ByteArrayOutputStream();
				byte[] data = new byte[4096];
				int l = 0;
				while ((l = this.content.read(data)) >= 0) {
					tmp.write(data, 0, l);
				}
				this.buffer = tmp.toByteArray();
				this.content = null;
				this.contentLength = buffer.length;
			} catch (IOException e) {
				// LOG.error(e.getMessage(), e);
				this.buffer = null;
				this.content = null;
				this.contentLength = 0;
			}
		}
	}

	/**
	 * Tests if this method is repeatable. Only <code>true</code> if the content
	 * has been buffered.
	 * 
	 * @see #getContentLength()
	 */
	public boolean isRepeatable() {
		return buffer != null;
	}

	/*
	 * (non-Javadoc)
	 * 
	 * @see
	 * org.apache.commons.httpclient.RequestEntity#writeRequest(java.io.OutputStream
	 * )
	 */
	public void writeRequest(OutputStream out) throws IOException {

		if (content != null) {
			byte[] tmp = new byte[4096];
			int total = 0;
			int i = 0;
			while ((i = content.read(tmp)) >= 0) {
				out.write(tmp, 0, i);
				total += i;
			}
		} else if (buffer != null) {
			out.write(buffer);
		} else {
			throw new IllegalStateException(
					"Content must be set before entity is written");
		}
	}

	/**
	 * Gets the content length. If the content length has not been set, the
	 * content will be buffered to determine the actual content length.
	 */
	public long getContentLength() {
		if (contentLength == CONTENT_LENGTH_AUTO && buffer == null) {
			bufferContent();
		}
		return contentLength;
	}

	/**
	 * @return Returns the content.
	 */
	public InputStream getContent() {
		return content;
	}

}
